1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2007 Oracle.  All rights reserved.
4 */
5
6#ifndef BTRFS_DISK_IO_H
7#define BTRFS_DISK_IO_H
8
9#include <linux/sizes.h>
10#include <linux/compiler_types.h>
11#include "ctree.h"
12#include "fs.h"
13
14struct block_device;
15struct super_block;
16struct extent_buffer;
17struct btrfs_device;
18struct btrfs_fs_devices;
19struct btrfs_fs_info;
20struct btrfs_super_block;
21struct btrfs_trans_handle;
22struct btrfs_tree_parent_check;
23struct btrfs_transaction;
24
25#define BTRFS_SUPER_MIRROR_MAX	 3
26#define BTRFS_SUPER_MIRROR_SHIFT 12
27
28/*
29 * Fixed blocksize for all devices, applies to specific ways of reading
30 * metadata like superblock. Must meet the set_blocksize requirements.
31 *
32 * Do not change.
33 */
34#define BTRFS_BDEV_BLOCKSIZE	(4096)
35
36static inline u64 btrfs_sb_offset(int mirror)
37{
38	u64 start = SZ_16K;
39	if (mirror)
40		return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
41	return BTRFS_SUPER_INFO_OFFSET;
42}
43
44void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
45void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
46struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
47				      struct btrfs_tree_parent_check *check);
48struct extent_buffer *btrfs_find_create_tree_block(
49						struct btrfs_fs_info *fs_info,
50						u64 bytenr, u64 owner_root,
51						int level);
52int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
53int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
54			   const struct btrfs_super_block *disk_sb);
55int __cold open_ctree(struct super_block *sb,
56	       struct btrfs_fs_devices *fs_devices,
57	       char *options);
58void __cold close_ctree(struct btrfs_fs_info *fs_info);
59int btrfs_validate_super(struct btrfs_fs_info *fs_info,
60			 struct btrfs_super_block *sb, int mirror_num);
61int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount);
62int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
63struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
64struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
65						   int copy_num, bool drop_cache);
66int btrfs_commit_super(struct btrfs_fs_info *fs_info);
67struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
68					struct btrfs_key *key);
69int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
70			 struct btrfs_root *root);
71void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
72
73struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
74				     u64 objectid, bool check_ref);
75struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
76					 u64 objectid, dev_t *anon_dev);
77struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
78						 struct btrfs_path *path,
79						 u64 objectid);
80int btrfs_global_root_insert(struct btrfs_root *root);
81void btrfs_global_root_delete(struct btrfs_root *root);
82struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
83				     struct btrfs_key *key);
84struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
85struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr);
86struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info);
87
88void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
89void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
90void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
91void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
92				 struct btrfs_root *root);
93int btrfs_validate_extent_buffer(struct extent_buffer *eb,
94				 struct btrfs_tree_parent_check *check);
95#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
96struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
97#endif
98
99/*
100 * This function is used to grab the root, and avoid it is freed when we
101 * access it. But it doesn't ensure that the tree is not dropped.
102 *
103 * If you want to ensure the whole tree is safe, you should use
104 * 	fs_info->subvol_srcu
105 */
106static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
107{
108	if (!root)
109		return NULL;
110	if (refcount_inc_not_zero(&root->refs))
111		return root;
112	return NULL;
113}
114
115void btrfs_put_root(struct btrfs_root *root);
116void btrfs_mark_buffer_dirty(struct btrfs_trans_handle *trans,
117			     struct extent_buffer *buf);
118int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
119			  int atomic);
120int btrfs_read_extent_buffer(struct extent_buffer *buf,
121			     struct btrfs_tree_parent_check *check);
122
123blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio);
124int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
125			      struct btrfs_root *root);
126int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
127			     struct btrfs_fs_info *fs_info);
128int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
129		       struct btrfs_root *root);
130void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
131			     struct btrfs_fs_info *fs_info);
132void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
133				  struct btrfs_fs_info *fs_info);
134struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
135				     u64 objectid);
136int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
137int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid);
138int btrfs_init_root_free_objectid(struct btrfs_root *root);
139
140#endif
141